Enum Visibility 

pub enum Visibility {
    Default,
    Hidden,
    Protected,
}

How far a name reaches outside a shared library when nothing in the source said.

-fvisibility=, which is written on every cmake project that cares about its exports and is the way a library ships a small documented interface instead of every name it happens to define. The attribute in the source wins wherever one was written, which is what makes the flag a default rather than an override and what lets -fvisibility=hidden be put on a whole tree and the dozen exported names marked one at a time.

Three answers to four spellings. internal is hidden plus a promise about never taking the address across a component boundary, and nothing here derives anything from that promise, so what it gets is the same symbol with a weaker claim on it.

Variants

Default

-fvisibility=default. Exported and interposable, which is what a name gets when the flag is not written at all and what gcc does by default too.

Hidden

-fvisibility=hidden and -fvisibility=internal. Not in the dynamic symbol table.

Protected

-fvisibility=protected. In the dynamic symbol table, and a reference from inside the library binds to the definition inside it.

Implementations

impl Visibility

pub const fn as_str(self) -> &'static str

The spelling this is asked for by, without the flag in front of it.

One spelling each, so internal is not here: it is a way of asking for hidden rather than an answer of its own.

Trait Implementations

impl Clone for Visibility

fn clone(&self) -> Visibility

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Visibility

impl Debug for Visibility

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Visibility

fn default() -> Visibility

Returns the “default value” for a type.

impl Display for Visibility

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Visibility

impl FromStr for Visibility

fn from_str(s: &str) -> Result<Self, ()>

Parses the part after -fvisibility=.

type Err = ()

The associated error which can be returned from parsing.

impl Hash for Visibility

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Visibility

fn cmp(&self, other: &Visibility) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

fn clamp_to<R>(self, range: R) -> Self

where Self: Sized, R: ClampBounds<Self>,

🔬This is a nightly-only experimental API. (clamp_to)

Restrict a value to a certain range.

impl PartialEq for Visibility

fn eq(&self, other: &Visibility) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for Visibility

fn partial_cmp(&self, other: &Visibility) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for Visibility